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Punch Card
Posts: 16
Registered: ‎08-26-2015
Location: Saint-Jean-sur-Richelieu
Views: 1,324
Message 1 of 4

Lenovo Y40-70 battery problem

I've had a battery issue (the known one : battery says 100% and suddenly falls at 0% and shut down) and in September I sent my computer to Lenovo. It tooks about 6-7 weeks for the battery to be replaced. My warranty was supposed too be extended, but was not. Now, my battery has the exactly same problem. I do not want my battery to be replaced again : it takes a too much long time and I can't wait that much long again. Can someone help me please to resolve this problem?

Thank you.

Retired Support Specialist
Posts: 3,772
Registered: ‎12-24-2015
Location: IN
Views: 1,275
Message 2 of 4

Re: Lenovo Y40-70 battery problem

Welcome to the Lenovo Philbilo.


Reset the BIOS to default before you do anything else. 

  1. Unplug AC adapter (remove from notebook).
  2. Remove main battery
  3. Press and hold the power button for 30 seconds (power drain)
  4. Replace main battery
  5. Replace AC adapter

Based from your findings, it's possible that:

- The battery circuit inside is not working to unload the charge, or

- One of the battery cells have already reached its life span

- the chip that handles how the battery gets charge/discharge and checks the charge level of each battery cell (both are controlled by a firmware) is malfunctioning.


Batteries degrade overtime due to heat and daily use. If you're still under warranty, i would suggest you to visit the nearest authorised Lenovo authorised support for hardware assistance.


More info:

How Lithium-ion Batteries Work


Let us know how you get on.




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Former Employee
Posts: 1,664
Registered: ‎09-16-2014
Location: US
Views: 1,037
Message 3 of 4

Re: Lenovo Y40-70 battery problem

In response to customer reports of unexpected battery gauge behavior on Y40-70 and Y40-80 laptops, Lenovo determined the battery gauge software is performing as expected. The unusual gauge results being reported are a reflection of the battery reaching end of life.


Lenovo has released a Service TIP to assist customers with obtaining battery replacements under warranty, or if out of warranty, to find a replacement battery from Lenovo-approved vendors. The Service TIP can be found here:


The part numbers for Y40-70/80 batteries are:

Y40 SP/A L13M4P01 7.4V48Wh 4cell bty (Y40-70/Y40-80) 121500248

Y40 LG L13L4P01 7.4V48Wh 4cell bty (Y40-70/Y40-80) 121500249 substitute part 121500251

Y40 CP/C L13C4P01 7.4V48Wh 4cell bty (Y40-70/Y40-80) 121500259 substitute part 121500251


To determine which battery came with your Y40 notebook, instructions for removing the bottom cover can be found in the Hardware Maintenance Manual pdf here. An alternative to opening your system (which does not void warranty) is to search for batteries using the model/product number located on the bottom cover.


Thank you,

Serial Port
Posts: 18
Registered: ‎04-08-2017
Location: ID
Views: 813
Message 4 of 4

Re: Lenovo Y40-70 battery problem

i have this problem too in my y40-80, how long this laptop warranty cover the battery problem?

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